The present invention relates to a planting system for regulating the supply of water to a plant and to a paving system incorporating such a planting system.
It is known to plant plants in a plant growing medium contained within a liner, supported by the surrounding substrate layer, in order to provide a controlled environment for that plant. In order to prevent excess water collecting in the linear and causing the plant to become water logged, it is known to provide drainage holes in the linear to allow water to drain from the plant growing medium to the substrate layer. In sites where it is generally desirable to prevent water from draining into the surrounding substrate layer, for example where the substrate is a potential source of pollution, such as a landfill site, it is not possible to use such a planting system.
It is known from European Patent No 0 786 034 to provide a paving system for spillage or floodwater management comprising a permeable layer providing an upper surface; at least one supporting substrate layer thereunder which is permeable to liquid and a containment membrane of impermeable material containing said substrate layer for controlled retention of liquid therein. In a preferred embodiment of the paving system described in that specification, the paving system is provided with valves and discharge ducts for drainage. The paving system according to European Patent No 0 786 034 is particularly suitable for use in areas where there is a risk of spillage of fluids which must be prevented from entering the environment before treatment. It is a disadvantage of the paving system according to European Patent No 0 786 034 that, where it is used in areas where there is no such risk, the surface water which drains from it must either be discharged to waste or to a storage tank for further use.
The present invention seeks to provide an improved planting system.
Accordingly, the present invention provides a planting system for regulating the supply of water to a plant, the system comprising a liner containing a volume of plant growing medium;
characterized in that:
the liner is impermeable to water;
the system further comprises drainage means adapted to drain water from the plant growing medium contained within the liner and conveyor the drained water to a desired location;
and wherein the liner serves to prevent drainage of water from the medium into the surrounding subsoil.
The present invention further provides a paving system comprising at least a surface layer provided with an island in the form of a hole or trench for receipt of a plant, in combination with a planting system according to the immediately preceding paragraph.